Nanotech

A technician making electronic circuits for computers. / Photo by: Anna Ivanova via 123RF

 

A new manufacturing technique has been created to make the production of electronic circuits easier and quicker.

Electronic circuits used in producing laptops, smartphones, tablets, and other mobile gadgets undergo fabrication techniques that apply a thin rain of liquid metal drops to help form respective shapes. However, these metal fabrication methods can cause rough surfaces to develop on the circuits, which adds to the overheating problem and battery drain issues of finished products.

To address this issue, a team of researchers used a new technique involving a high-energy carbon dioxide laser shot to trigger a “superelastic” behavior in metallic materials for a short period of time. This temporary “superelasticity” allowed the metals to flow into the nano mold part of the rolling stamp, overcoming the limitation of formability. The circuits manufactured in this way displayed some flexibility and featured smooth surfaces.

The technique was developed at Purdue University and it resembles a process similar to printing the local newspaper. The blueprint includes the use of a plastic substrate, laser imprinting, carbon dioxide laser, graphite layer, a metal layer, a nano mold, and nanopatterned metal. They called it roll-to-roll laser-induced superplasticity.

"Adding the latest advances in nanotechnology requires us to pattern metals in sizes that are even smaller than the grains they are made of. It's like making a sand castle smaller than a grain of sand," said Ramses Martinez, an assistant professor of industrial engineering and biomedical engineering at Purdue.

The team considered the process to be cost-effective because it employs tools that are already available in industrial settings, including the carbon dioxide lasers. In the future, the technique can permit the mass production of devices with flexible touch screens or display screens with nanoscale components.